Seismic response of a subway station in soft soil considering the structure-soil-structure interaction

Abstract An investigation on the dynamic interactions existing in a system consisting of multiple above-ground buildings, soil and a subway station when subjected to ground motions, normally named surface structures–soil–underground structure interaction (SSSI), is presented in this paper. Based on a series of shaking table tests on the seismic response of a system comprising a building, a tunnel and soil, a numerical simulation was conducted. The results were compared with experimental records for verification of the numerical modeling. According to the modeling procedure, the ABAQUS software was further developed and an auto-modeling system creating a multiple above-ground buildings–soil–subway station system rapidly was obtained and enhanced for calculation in time domain. The subroutine of the modified Davidenkov constitutive model was called to consider the nonlinearity of the soft soil in the computational process. The influencing mechanism of the interaction on the seismic response of the subway station was studied using the auto-modeling system. The inter-story drift ratio and peak acceleration were selected to evaluate the dynamic interaction in this complicated system. The influencing factors, including the horizontal distance between the buildings and the subway station, number of the buildings, height of the buildings, and burial depth of the subway station were considered in this study. Numerical results indicate that several key factors such as number of buildings, and burial depth may evidently amplify or attenuate the seismic response of an underground structure.